Many forms of tank trailers have been devised for transporting flowable materials including liquids and a wide variety of pulverulent and granular solid materials. One such tank trailer has a horizontally disposed substantially cylindrical tank with upwardly inclined ends and plurality of hoppers formed in the bottom of the tank to facilitate the unloading of the tank. The tank is provided on its top with a number of filler openings for loading of the tank. The tank may also be divided into a number of compartments so that each compartment can be loaded and unloaded separately and independently of the other compartments. The inclined or sloping end structure of the tanks facilitates the downward flow of dry and liquid flowable materials when these materials are being unloaded through the hopper bottoms. A suitable frame structure is then attached to each end of the tank at the lower portion thereof so that one frame structure serves as a supporting carriage for wheels and other frame structure is provided with a trailer hitch for connecting the trailer to a tractor.
Previously devised tank trailers are prone to roll over due to a relatively high center of gravity and a relatively narrow frame and wheel-base.